Power supply



FIG. 1 is a front view of a power supply showing my new design;

FIG. 2 is a left view thereof;

FIG. 3 is a right view thereof;

FIG. 4 is a top view thereof;

FIG. 5 is a bottom view thereof;

FIG. 6 is a rear view thereof;

FIG. 7 is a frontal perspective view thereof; and,

FIG. 8 is a view of the power supply in use.

The broken lines shown represent unclaimed subject matter and form no part of the claimed design. 

CLAIM The ornamental design for a power supply, as shown and described. 